PDBBuzzer.h

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/*
 * File:   PDBBuzzer.h
 * Author: Chris
 *
 * Created on September 25, 2015, 5:10 PM
 */

#ifndef PDBBUZZER_H
#define PDBBUZZER_H

#include <memory>
using namespace std;

// create a smart pointer for PDBBuzzer objects
class PDBBuzzer;
typedef shared_ptr<PDBBuzzer> PDBBuzzerPtr;

// A buzzer is an object given by someone who wants work done by a worker.
//
// The buzzer's constructor takes as input a function to handle the buzzer being signaled.
//
// Typically, someone who wants work done will create a buzzer, and then give it to a bunch
// of workers, then will call wait () to sleep until work is completed.
//
// When a piece of work is completed, the woker then calls buzz (), which invokes the
// function stored inside of the buzzer.
//
// One is guarnateed that each call to buzz () will result in a separate invocation of
// the function.

#include "PDBAlarm.h"
#include <pthread.h>
#include <string>
#include <functional>


class PDBBuzzer {
public:
    // sounds the buzzer, causing noStringFunc () to be called
    void buzz(PDBAlarm withMe);

    // sounds the buzzer, causing stringFunc () to be called
    void buzz(PDBAlarm withMe, string message);

    // sounds the buzzer, causing workFunc () to be called
    void buzz(PDBAlarm withMe, int& counter);

    // blocks until someone calls buzz
    void wait();

    // constructor, destructor
    PDBBuzzer();
    PDBBuzzer(std::nullptr_t nullp);
    PDBBuzzer(std::function<void(PDBAlarm)>);
    PDBBuzzer(std::function<void(PDBAlarm, string)>);
    PDBBuzzer(std::function<void(PDBAlarm, int&)>);
    ~PDBBuzzer();


private:
    pthread_mutex_t waitingMutex;
    pthread_cond_t waitingSignal;
    bool signalSent = false;
    std::function<void(PDBAlarm)> noStringFunc = nullptr;
    std::function<void(PDBAlarm, std::string)> stringFunc = nullptr;
    std::function<void(PDBAlarm, int&)> intFunc = nullptr;
};


#endif /* PDBBUZZER_H */